Outcomes of a Clinical Protocol for Benign Solid Breast Masses

Background: Pediatric breast masses are generally benign, however, surgical resection is common, even for small lesions. Additionally, breast surgery in young girls has the potential for negative psychological impact. Therefore, we developed an evidence-based clinical protocol to decrease unnecessary surgery for appropriately selected masses (Figure). The purpose of this study is to evaluate outcomes pre- and post-protocol implementation.

Methods: Following IRB approval, a retrospective review was performed of patients <18 years old evaluated for a solid breast mass. Patients were grouped into two cohorts: pre- (3/2019–2/2020) and post- (3/2020–3/2021) protocol implementation. Demographics, family history, symptoms, imaging characteristics, management, pathology, and outcomes of observation and surgery were collected. Analyses were performed with independent two-sample t-test and Chi-Squared.

Results: 106 patients were identified (56 pre-protocol, 50 post-protocol) with comparable rates of family history of breast cancer (pre-protocol 29%, post-protocol 22%; p=0.44) and median maximum diameter (cm) (pre-protocol 3.3, post-protocol 3.0; p=0.94) between the cohorts. Protocol adherence was 72% (36/50) during the post-protocol period (Figure). Significantly fewer patients had surgical resection after protocol implementation (pre-protocol 47/56, 84%; post-protocol 27/50, 54%; p=0.001). The most common surgical pathology in both study periods was fibroadenoma (pre-protocol 87%, post-protocol 88%) with no phyllodes tumors or malignancies. For masses <5cm evaluated pre-protocol, 81% (38/47) were resected; 42% (16/38) for provider/parental preference and 39% (15/38) for symptoms. For masses <5cm evaluated post-protocol, 70% (19/27) were resected; 37% (7/19) for symptoms and 32% (6/19) for provider/parental preference. Following observation, there was a comparable rate of no growth (pre-protocol 4/24, 17%; post-protocol 3/30, 10%; p=0.37), decrease in size or resolution (pre-protocol 3/24, 13%; post-protocol 4/30, 13%; p=0.63), and interval growth (pre-protocol 1/24, 4%; post-protocol 5/30, 17%; p=0.16) between the study periods at initial follow-up visit. However, significantly fewer masses were resected post-protocol following observation (pre-protocol 15/24, 63% vs post-protocol 7/30, 23%; p=0.004). Interval growth for all observed lesions (n=6) was 0.4 (cm) (range 0.1–1.5) after median 5-month follow-up (range 3–9). None of the lesions grew >50% or were >5cm after observation.

Conclusion: An institutional clinical protocol for management of benign pediatric solid breast masses was effective to decrease unnecessary surgical intervention for small pediatric breast masses. Serial observation led to minimal growth and no adverse outcomes; this data could be useful for parental reassurance.